Framework and method for QoS-aware resource discovery in mobile ad hoc networks

Abstract

A framework and method for quality of service (QoS) aware resource discovery in mobile ad hoc networks are presented. Self-organized discovery agents manage the directory information that describes the network resources available for use by clients. In one embodiment, hash indexing of available resources is utilized. The discovery agents also partition the network into domains and collect intra- and inter-domain QoS information. This information is used to allow clients to select appropriate resource providers. This framework and method has low discovery latency and cost in terms of the number of packets for each resource discovery query.

1. In a mobile ad hoc network having a plurality of mobile nodes, at least one mobile node of which being a resource provider, a quality of service (QoS) aware resource discovery method, comprising the steps of:
 generating at least one discovery agent from the plurality of mobile nodes to service queries from other mobile nodes and to register resources provided by the resource provider; 
 forming at least one dynamic domain within the ad hoc network, each dynamic domain including at least a subset of the mobile nodes as members thereof and one discovery agent, the one discovery agent serving as a home discovery agent for its associated dynamic domain wherein the forming comprises broadcasting, by a discovery agent, a formation announcement containing at least a distance field; comparing, by a receiving node, the distance field to a distance from the node's current home discovery agent; when the distance field is less than the distance from the node's current discovery agent, and when the receiving node does not have a current home discovery agent, setting the discovery agent that broadcasts the formation announcement as the node's new home discovery agent; 
 registering a resource by the resource provider with the home discovery agent of the resource provider's associated dynamic domain; 
 generating by one of the mobile nodes within the ad hoc network a query mobile node's home discovery agent to discover the resource; and 
 discovering by the one of the mobile nodes' home discovery agent the resource within the mobile ad hoc network regardless of the resource's location within or without of the one of the mobile nodes' dynamic domain. 
 
   
   
     2. The method of  claim 1 , wherein the step of generating at least one discovery agent comprises the steps of:
 broadcasting, by all eligible nodes, existence information including a node address; 
 electing the node that has the smallest node address as an initial discovery agent. 
 
   
   
     3. The method of  claim 1 , further comprising the step of forwarding the formation announcement to the node's neighbors after the step of setting the discovery agent that broadcast the formation announcement as the node's new home discovery agent. 
   
   
     4. The method of  claim 1 , further comprising the step of collecting, by a resource provider's home discovery agent, application-level quality of service (QoS) information from the resource provider. 
   
   
     5. The method of  claim 1 , further comprising the step of estimating, by each home discovery agent, path quality of service (QoS) between nodes in its associated dynamic domain and those of another dynamic domain as the path latency between itself and the home discovery agent for the other dynamic domain. 
   
   
     6. In a mobile ad hoc network having a plurality of nodes, a subset of the nodes assuming a role of a discovery agent, a method of forming a dynamic domain within the ad hoc network, comprising the steps of:
 broadcasting, by a discovery agent, a formation announcement containing at least a distance field; 
 comparing, by a receiving node, the distance field to a distance from the node's current home discovery agent, if any; 
 when the distance field is less than the distance from the node's current discovery agent, and when the receiving node does not have a current home discovery agent, setting the discovery agent that broadcast the formation announcement as the node's new home discovery agent; and 
 forwarding, by the receiving node, the formation announcement to the node's neighbors after the step of setting the discovery agent that broadcasts the formation announcement as the receiving node's new home discovery agent.